Tracked vehicles are known to be advantageous for negotiating rough terrain and load bearing. Such vehicles are useful in applications such as military, agricultural or construction vehicles. It is also possible to employ remotely operated or robotic tracked vehicles in situations where it is dangerous to use a manned vehicle or to deploy a human pedestrian. Such applications include bomb disposal, some rescue operations, and the deployment of remote weapons platforms, for example robot vehicles carrying remotely operated weapons turrets. Military requirements for such weapons deploying robots call for extreme obstacle negotiating capabilities, including the capability to ascend steep stairs.
The use of conventional track mechanisms in such applications is limited, in that different situations may best be tackled with different shapes of track profile. For example, when driving up steep stairs, it is advantageous to have a long tracked base and a low center of gravity, to avoid the robot toppling over backwards. In contrast, when driving over rough terrain, it may be advantageous to have high ground clearance, necessitating a comparatively high center of gravity. It would therefore be advantageous to have a single vehicle for which the shape of the tracks could be varied during operation.
Additionally, when operating a vehicle mounted weapons or surveillance turret, problems may arise when the vehicle is on inclined terrain, as the plane in which the turret pans may become skewed to the horizontal. In such instances it would be desirable to have a vehicle with a self leveling mechanism, whereby the main body of the vehicle, and hence the plane of a turret, mounted thereon, could be leveled with respect to the horizon.
The present invention comprises a novel polymorphic track mechanism, whereby it is possible to vary the shapes of the tracks during operation. Furthermore, since it is possible to vary the shapes (and hence the depths) of the left and right tracks independently of each other, this invention enables such a vehicle to be operated so as to effect self leveling.